In this work, we present an analysis of the sensitivity to the active-sterile neutrino mixing with the Indian Scintillator Matrix for Reactor Anti-Neutrino (ISMRAN) experimental setup at very short baseline. The 3 $(\text{active})+1$ (sterile) neutrino oscillation model is considered to study the sensitivity of the active-sterile neutrino in the mass splitting and mixing angle plane. In this article, we have considered the measurement of electron antineutrino induced events employing a single detector which can be placed either at a single position or moved between a near and far positions from the given reactor core. Results extracted in the later case are independent of the theoretical prediction of the reactor anti-neutrino spectrum and detector related systematic uncertainties. Our analysis shows that the results obtained from the measurement carried out at combination of the near and far detector positions are improved significantly at higher $\mathrm{\Delta }{m}_{41}^2$ compared to the ones obtained with the measurement at a single detector position only. It is found that the best possible combination of near and far detector positions from a $100{\mathrm{MW}}_{\mathrm{th}}$ power DHRUVA research reactor core are 7 m and 9 m, respectively, for which ISMRAN setup can exclude in the range $1.4{\mathrm{eV}}^2\le \mathrm{\Delta }{m}_{41}^2\le 4.0{\mathrm{eV}}^2$ of reactor antineutrino anomaly region along with the present best-fit point of active-sterile neutrino oscillation parameters. At those combinations of detector positions, the ISMRAN setup can observe the active sterile neutrino oscillation with a 95% confidence level provided that ${\sin }^{2}2{\theta }_{14}\ge 0.09$ at $\mathrm{\Delta }{m}_{41}^2=1{\mathrm{eV}}^2$ for an exposure of 1 ton-yr. The active-sterile neutrino mixing sensitivity can be improved by about 22% at the same exposure by placing the detector at near and far distances of 15 m and 17 m, respectively, from the compact proto-type fast breeder reactor (PFBR) facility which has a higher thermal power of $1250{\mathrm{MW}}_{\mathrm{th}}$.

• Received 11 February 2020
• Accepted 30 June 2020

DOI:https://doi.org/10.1103/PhysRevD.102.013002

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

Published by the American Physical Society